2013.11.04 - UPDATE! - THE HILLBILLY CNC MACHINE....
It was a mix of good and bad this weekend in the shop.
At the point were I left off, the monolith was completely plated-up for the rear suspension heims, so the only remaining item was to plate the front hangers a bit more, and then drill some speed/drainage holes. Things were getting pretty close to completion, and truth be told I'm getting a bit bored with the monolith project now and will be happy to move along to something (ANYTHING!) else...
The front hangers needed a tricky set of top plates to help strengthen and triangulate the vertical bracketry. You can see them in this photo.
This helps tie the plates into the side areas, and into the long "X" structure that runs all the way through the crossmember. With a couple of small boxing plates, the areas are beefed up and are now sealed from the elements.
With everything tacked in place it was time to rotate the monolith into a more favorable position for corner-to-corner welding. As Rene astutely pointed out, if you go to the trouble of getting the weld horizontal and keep the deepest part of the weld at the very bottom it becomes MUCH easier to lay down a good weld and you don't end up fighting the "sag" in the puddle.
Things were going great, and I was laying some nice beads using this technique.... then as I was finishing up a short welding pass, the welder completely QUIT. Nothing.... no spark, no puddle.
I thought I must have boogered-up the contact tip and fused the wire to it accidentally, but on closer diagnosis I found this instead.
Yep, it's official. I've now run throught my SECOND 12.5 Lb spool of .030" wire since this project began!

It's a weird "badge of honor" type thing I suppose.... getting that much trigger time means that I'm really working hard on the project and getting a lot more experience along the way, but unfortunately I didn't have an extra spool in the workshop to reload with... so progress came to a screeching halt.
Since I still had several hours left in my workshop day, and the space heater had the shop at a comfortable 60 degrees (outside was roughly 30 degrees) I decided to come up with a solution to drill my speed/drain holes in the monolith bottom plate..... It's not sexy, but here's how I did it.
Basically, I just walked the drillpress out into the middle of the shop then pushed my workbench underneath...then cranked up the table so that it acted a little bit like a vise to hold the press a bit more firmly....
The result was only OK. I'm using the 2-1/2" annular saw which is a pretty big load on my low-end drillpress. They really aren't designed to cut through 1/4" plate either. I tried WD-40 as a cutting fluid, then moved up to my tap oil...and eventually settled on regular old motor oil to try to keep the heat down and keep the cutter from binding and locking up once it got about 1/2 way into the plate.
At this point, I've got a lot of partially drilled holes, and it may be easier to try to finish them from the opposite side using the existing pilot holes as an index. I think there is just too much friction on the sides of the cutter when the cuts get too deep.....
Anyway..... I ordered 2 more spools of wire (I'm finally learning!!!) and 20 more contact tips just to be safe. I'd better get to my local AirGas and refill my 80cu ft gas bottles too while I'm thinking about it...
-G