hey all, i've got an 87 k5 that i recently swapped motors on. (blown up 350 with not blown up '69 4 bolt but nothing too fancy). the trans (700r4) shifts fine 1-2, but when it wants to shift into third, it goes into neutral and starts revving instead. it does this in 2wd or 4hi, i havent tried in 4lo but expect it wouldn't matter. i can drive around town holding it in 2nd, but obviously i cant get on the freeway. the tranny fluid level is fine. when i was swapping the motor i broke the end off the kickdown cable (where it attaches to the throttle linkage), but i put on a new end with a short extension so that is very close to the length it was, but maybe not exactly right. i left the tranny in the car so the sift linkage didn't get disturbed. any ideas? Help!