OK I got the old 61 GMC half ton done enough to drive some. well in sort of a loose way any way. the old 305 VK runs pretty good as far as I can tell so far. got the speedometer working, and it checks real close by a GPS. I have a glass pack muffler under there with not much tailpipe like I got it. some rubber seal gone under the doors as well as no floor mat. so plenty of noise on the road. anyway I have 215/85 R16 tires and 4.11 gear so must be close to factory tire size since the spedo is so close. with all the noise in the cab it's hard to know how much the engine is winding but it feels like it likes to run between 60 and 65. I would guess the old engine can handle a little more speed but don't want to strain it either. doesn't smoke or knock and I think I got the after market holley 2 bbl. set up about right. plugs points and timing good. I know I can't run it the legal Texas 75 but kinda wondering if anybody running one similar thinks it would handle a little more without straining it? eventually I'll get the floor mat in, door seals on and a few other quiet down items to make it more enjoyable. right now I just want to use it some without feeling like the turtle in the road. Raymond