Finally making progress again as of the new year. I took a break to remodel the master bathroom, like gut it to the studs, and after doing that for 4 months in all my spare time, I was ready to NOT do anything for a bit.
Began test fitting and mounting the engine though, and it's amazing how well this thing fits:
Where it goes:
Nearly in, but a good view of the stock bracket configuration that we're working with:
A front view - it's a little forward, so it looks bigger, but it fits between the frame rails nicely:
From the factory, the GMC has a removable trans tunnel cover that's different between the i6 and the v8. For the i6, it definitely needs to come off. It also needs to drop about an inch to comfortable space the guibo on the end of the driveshaft from the cab floor. Here it clears by less than a centimeter
Tucked back, to clear the front rail, the transmission lines need to be rerouted, and that oil sensor is probably just going to be something you'd have to do without. Back to checking the oil with a dipstick every so often like some sort of caveman:
So, with the factory setup, it looks like you'd need to notch that second crossmember down about an inch to get space for the transmission pan and to make some room for the driveshaft guibo, but very doable.
I've also got a new crossbrace that's designed to take smallblock Chevrolet mounts and weld and bolt in, using 79 Corvette motor mounts, I just need to create a bracket that goes from the mounting bosses on the side of the block to the engine mounts, and it'll be perfect.
In MY case, however, the geometry is all wrong, they don't make original style tie rod ends anymore, and the replacements don't clear my wheels and tires. So instead, I'm going with one of the aftermarket front end clips based on the Mustang II. So as well as everything fits HERE... it's all going to change. :P
With the new front clip, and being able to remove the leaf spring mounts in front, I can take that second crossbrace out and move it back to become the new rear transmission mount crossbrace. So that'll provide access to the pan and eliminate the need for a new brace to be fabricated, and still box the frame correctly. I may end up not using the SBC engine mount thing at all, and just be able to mount directly onto the Mustang 2 front cross brace... after all, that's what the Mustangs do.
We'll have to see how it goes when the new front end gets here in a few weeks.