Bit of interesting info:
1. Jorge González, whose actual height is/was roughly 7'6.5" (230cm) was known as Giant Gonzalez in WWF and El Gigante in WCW. He is the tallest commonly known wrestler. He was billed 7'7" and "nearly" 8' tall.
2. Ron Reis, at 7'2", was also known as Ron Studd and the Yeti in WCW. Surprisingly billed this height even when The Big Show (then The Giant) was billed at 7'4" in WCW, and being as much as 2" shorter than Reis. As the Yeti he was merely billed as "THAT MAN IS TALLER THAN THE GIANT!"
3. Dalip Singh, currently known as The Great Khali in the WWE has been billed anywhere from 7'2" - 7'4" in the WWF and significantly taller than that in Japan but has found a home at 7'3" as of late. His actual height likely just above 7'1" (217cm) which has been documented before he arrived in the WWE, and also has been listed as low as 6'11.5" in his younger weight lifting days.
4. Paulo César da Silva, also known as Giant Silva in Japan and and Paulo Silva in the WWF, is generally billed 7'3" - 7'5" and comes in around 7' - 7'1" (215cm). Generally wears thicker boots to increase his height for effect.
5. Paul Wight's, or the Big Show's, height is suspect in the sense he is clearly not as tall as he once was, and also wears thicker boots than most wrestlers. He was more than likely 7' (213cm) in WCW as the Giant in his 20s, and now around 6'11" (210-211 cm) in the WWE. He has been billed 7', 7'2" and 7'4" (WCW)
6. Andre the Giant was generally billed 7'4" and eventually 7'5" starting at Wrestlemania 3, then back down again towards the very end of his career. He has one of the most widely disputed heights, being listed as low as 6'9.75" but it is generally agreed he was at least 6'11.5" (213cm) in his youth.
7. Kevin Nash, also known as Diesel and various other aliases has generally always been billed as 7', with the occasional random bumps and dips above and below. His website lists him at a generic 6'10" (208-209cm), so he could be slightly taller than that.
8. Robert Maillet, known to many as Kurrgan is approximately the same height as Kevin Nash (208cm), but was also billed 7' tall in the WWF.
9. Stan Frazier is a forgotten name in the wrestling business, that of Uncle Elmer (and countless other names) who was billed anywhere from 6'10" to 7'2", but could very well have been 6'10" (208cm) since he wasn't much shorter than Andre the Giant while he was still close to his peak. Due to his lack of marketability, his height was never emphasized like Andre's.
10. Nathan Jones is self professed as 6'10" (208cm) and has been billed as much as 7'1".
11. Giant Baba of Japanese wrestling fame was commonly listed as 6'10.5" but oddly as low as 6'6.5". He was more than likely about 6'9" (206cm).
12. Matt Morgan, now known as Beast on the New American Gladiators has been billed around 7' for most of his wrestling career, coming in around 6'9" (206cm) legit.
13. Coming in at lucky 13, The Undertaker has had a consistent verbal and written height bill of 6'10.5" for the last 18 years in the WWE/F, and billed 6'9" in WCW as Mean Mark. He has stated himself as being 6'8" or 9, so 6'8.5" (204 - 205cm) is probable.
14. Kane is generally billed as 7 feet tall in the WWE, with the occasional similar comparisons to his TV brother the Undertaker being around 6'10" or 11. He is roughly over 6'8" (204cm) but due to thicker boots to give the impression he is larger than the Undertaker he is billed taller.
15. The Big Cat Ernie Ladd, often billed 6'9" was probably 6'8" (203cm). It is worth noting he was listed as 6'9" in his football days.
16. Giant Haystacks, who eventually became Loch Ness in WCW, was billed as high as 6'11" during his roughly 30 year career, but closer to 6'8" (203cm).
17. Sid (Sycho, Justice, Vicious etc) has been billed wildly 6'9", 6'10" and 6'11" in his career, depending on who the competition was beneath or above him but most often 6'9". He is more than likely just above 2 meters taller at 6'7.5" (202cm).
18. Big John Studd was very possibly an even 6'7" or a little more (201cm) and was always criticized for enhancing his height with various subtle techniques like extra thick boots, standing on his toes, tall hair style, etc. He was generally billed 6'10".
19. Big Daddy V/Viscera is often underestimated in height due the illusion of his size at 500 lbs. He is just over the 2 meter barrier at 6'7" (200-201cm). He has been billed 6'7, 6'8" as a face and 6'9" mostly as a monster heel, with a random written billing of 6'6" for what are most likely arbitrary reasons.
20. George Gray, more commnonly known as The One Man or Akeem the African Dream, is another very large wrestler whose stature oftentimes skewed his menacing height. Early in his career he very well could have been over 6'7", but dances around that mark between 6'6.75 and 6'7" (200cm). Gray begins the "grey area" where this list is defining extremely tall wrestlers.