if a stock rad can take a warmed over V8, it should handle a 292, and with a 4:10 rear and 4 speed there shouldn't be any torque lack with any engine .... I've pulled some good hils at moderate speed without down shifting with
both my trucks [green 235, red 283, both 3.90 rears] loaded 1200-2000# without downshifting .... a good 283 will perform fine, and not require any modifications to install [other than a fan shroud or the original rad repositioning] if it comes with the correct bellhousing
Bill