dwg49gmc

yes your 1st gear is 7:1 but you don't need to worry @ freeway speeds your final is 1:1.
a 2.73 works on flat ground, find a hill (not a mountain) and you may be in trouble climbing it.

you'll now have to carry tow spare tyres
one f@$?
one chevy
you could simply re-drill the axles to chevy five lug.................

my.02
after doing a search on this site about rear ends that could work find
a 6 lugger or change everything to 5 lug chevy. A lot depends on what you will do w/ this truck later on .... an engine change? tranny? hotrod? street it? daily driver? lots to consider.
mine is a 292, T5 and 3:40.

http://www.stovebolt.com/bboard/cgi-bin//ultimatebb.cgi?ubb=get_topic;f=2;t=013343;p=1#000002

welcome to the bolt
enjoy your stay

Jim & Caroline
The highway is for gamblers, better use your good sense."
Gooday-that's my 1¢ answer due to the lousy economy ~ cause I ain't got - no . mo . doe
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