When I started this swap, I didn't have an 88 cradle. Not knowing if I'd be able to find one, I built a cradle with square tubing. While there is nothing wrong my square tube cradle, I've chosen to put it aside for now. After stumbling onto an 88 cradle from a local member, I decided to mount the Ecotec and F23 onto it instead.
Knowing the benefits of using jigs, I decided to make a cradle jig using material that I had on-hand. This will accurately index all the suspension mounting points and other critical mounting locations that I need. This will also hold the side rails in place while I make and modify 2"x3" tubing for the cross members. It will also get some legs so I can work at a more suitable height. With this jig, I will then be able to place the entire engine and trans combo right on top of it. This will allow me to position the drive train wherever I want more easily.
Here's a few pic's of the jig.
The green tape, with the blue line, is the axle centerline.
I held the camera a little sideways. This jig is actually square.
Here is the Ecotec and F23 sitting roughly in place.
From this angle, you can see the diagonal down tubes. These double as supports to hold the axles. This is beneficial for measuring purposes.
From there, I started on the rear 2"x3" cross member. I chose to place it just under the rear sway bar. There is clearance for the bar to move and if I need more, I can slightly raise the sway bar.
I used thin cardboard, from a cereal box, and wrapped it around the tube. Then, I taped it together and trimmed to fit the contours as required.
Using a paint marker, I traced the outline required. The yellow stands out nicely on the steel. I still chose to use a black Sharpie and retrace on top of the yellow. Using a thin cut-off wheel, I removed the material not required.
I will tack this in then start on the front cross member.