Fighters who have made the full contact crossover?

[Hoggmeister]

Ray Mercer and Francis Botha, both pretty good at it as well so it seems.

[VictorCharlie]

Matt Skelton was a K1 kickboxer and had a couple MMA fights
Christ Lylte was 13-1 as a pro boxer
Marcus Davis was 17-1-2 as a pro boxer
Yosuke Nishijima is probably the most decorated pro boxer @ 25-2-1 and winning a couple small cruiserweight belts. He got destroyed in MMA though

[generalbulldog]

Khaosai Galaxy who made the transition from Muay Thai kick boxing. A name that I'm pretty sure only hardcore boxing fans have heard.

[KananKrus]

Yeah, I remember the name Khaosai Galaxy. Back in the 80's he was knocking everyone he faced in the ring.

During a time when KO's with regularity for the lighter divisions in boxing was a rarity, he disposed of many via the short route with ease. Many of the up and coming Filipino fighters, he halted with impunity, exposing their unworthiness and "generously" dashing their collective hopes on further entertaining thoughts in advancing well in the sport!

I think his greatness in the ring, off-handedly shed light to his sport of origin, which was Muay Thai. At a time when the rest of the world was still clueless on kickboxing, his exemplary exploits in boxing, gave a thread to the other, soon as his background was examined and to have found Muay Thai as its roots.

****

Terdsak Jaendang (pardon the spelling, I'm sure), is a Thai fighter who Steven Luevano defeated in an undercard fight, to the Pacquiao vs. JMM 2 fight last year, was also a full-pledged, former Muay Thai fighter, who crossed-over to boxing. The lure of the bigger pay, and the wider based fame I believe, is more than enough reason for these former kickboxing champions to switch.