Just a suggestion.....if you decide to go with a T5 bear in mind that the S10 boxes come in 2 basic ratios and if you plan on running a 3.70 R&P you'll want the .72 OD. You'll find the .72's behind the 2.8L V6's while the .86 OD's are generally found behind the 4 cylinders. The S10 .86 boxes work best with the lower number R&P's....such as the 3.08's and have a 4.03 1st gear which makes for very quick shifts into second. The .72 boxes are a bit higher with a 3.76 1st gear and give you a little additional time in 1st gear.
A third option for a T5 is from the Camaro's with a 2.95 1st gear and a .63 OD. However, to use this box in your 51 truck you'd need to unbolt the Camaro tailshaft which puts the shifter back in the middle of the front seat and bolt on an S10 tailshaft. The speedo drive gear has to be relocated further forward.....sounds a bit technical but it really isn't that difficult of a mod. I've documented the mods and installations to both the S10 and Camaro T5's in my Truck and Street Rod Webshots albums. My current project vehicle is running the hybrid Camaro T5 behind a built SBC with a 3.73 diff.
After 10K miles in my AD truck with the S10 .72 T5 with most of it on the open road, I can attest that it's the best modification I've made. Being able to cruise well within the 235's torque band has opened up a whole new dimension for my old truck.
Dave
