ok so i have a 99 gmc sierra with the 5.3L i plan on adding electric fans in replacement of the clutch fan assembly. but befor i do this i would like to beef up the alternator a little bit. In 99 i know there are some options for alternators i currenty have the 105amp one. doe any one know if the 130 or 145 will fit. has anybody done this?? i guess we really just need to know if the mounts will match up and if the wire connections fit.

I have heard people on here upgrading to the 145amp. If the option is available for your year, the bolts should match up just fine. What you could do is have the parts guy pull both the 105 and the 145 and match it up right there.