A DD will require a close ratio trans.(RR would be good choice) I have two, plus Brownie or high rear ratios(hard to find). Plus some mount work. Sort of depends on end use. Unknown DD might burn as much oil as now. Other option would be to major 292 and use it until can get necessary DD parts in line-might take a year or so. Then can sell majored 292 for cash.

Ed

'37 GMC T-18 w/ DD 4-53T, RTO-610, 6231 aux., '95 GMC running gear, full disc brakes, power steering, 22.5 wheels and tires.
'47 GMC 1 ton w/ 302, NP-540, 4wd, full width Blazer front axle.
'54 GMC 630 w/ 503 gasser, 5 speed, ex fire truck, shortened WB 4', install 8' bed.
'55 GMC 370 w/270, 420 4 speed, grain, dump bed truck from ND. Works OK.