Hello Wouter,
Most sources say Rondon stood 6'3", but I look at the tale of the tape between him and Bob Foster, Foster stood about 2 inches taller than Rondon as Bob Foster actually stood 6'3 1/2" while Rondon stood 6'1 1/2". Find Rondon's tale of the tape in one of the old newspaper articles. There was a photo at the pre-fight press conference that Foster was taller than Rondon. Also, Rondon stood about 1 or 1 and a half inches taller than Jimm Dupree.
There is a video between Vicente Rondon and Jimmy Dupree.
https://www.youtube.com/watch?v=dGWiaZGihkQ
There is also the video of the fight between Vicente Rondon and Bob Foster in their unification Light Heavyweight title fight and you see how little Foster was taller than Rondon.
https://www.youtube.com/watch?v=5Oa46F79ZQ8
Please change Rondon's height and find out if his reach was 75 or 77 inches before you add it.