powerglide problems...help

[sevensixoh]

hey all ... so im having trouble with my 2 speed powerglide ,
when I engage it in drive , the truck revs high and slowly crawls to the next gear and finally kicks in after about ten seconds. So I obviously cant drive it around town . But when I put it in reverse , it works great!!

please help , DIY fixing or other options .... anyone know how much a rebuild on a powerglide runs $$$ ... oh and its behind a 283 automatic..

thanks in advance !!