Hi whomever! I was going to address by name but I don't see one....

I installed 4BT into my '67 D-100 Town Wagon & upgraded to roughly D-300. Frames are very similar to Sweptline, narrower in a couple of areas is all.

Terry, PwrWgnDrvr, has a Swepty with a 6BT, a very nice install. I don't think he did the swap but likely he has some pics.

I used an NV4500 in my 2WD install, fabricating my own engine mounts, frame mounts & crossmembers. I mistakenly used some tired 440 rubber isolators because cash was short. The stock 6BT isolators are a far better choice. Some use other isolators and thru drill-them with holes to allow more movement in the rubber, as 4BT's have some vibration & shutdown shake issues.

The frame mounts I made are similar to an old fashioned sugar scoop without the handle, as a box that fits into frame with a longer lip on bottom to catch the engine mounts & isolators. Box fits flush & tight to increase frame strength & support, bolted in back & at top to reduce flexion. Looking from front of truck, box sides taper down to the extended lip, supporting that surface like an angle brace.

Engine mounts are similar to stock 4BT for purpose of bolt hole alignment, but on passenger side some allowance has to be made for coolant conections, some relieving. Figure out your water outlet & heater hose lower block connections before you fire up your plasma cutter! These are a flat plate bolted to engine, right angle wall sticking out with other gussets for reinforcement, and flat bottom plate to catch frame mount lip, isolators sandwiched in between. Extended lip and engine mount lower surface are horizontal, isolator bolted in horizontal.

I used 1/2" plate for everything and personally wouldn't use lighter gauge. Also Grade 8 bolts, why take chances?

I was able to remove stock forward bellhousing crossmember & fab a deeper 'U' section to clear Cummins adapter plate, bellhousing etc. I mounted my engine low, achieving flat floors with no trans hump. Fabbed a rearward crossmember to support NV4500 tailshaft by modifying a '78 D-200 auto trans crossmember to fit NV4500 specs. Anotehr mistake, money again, I used '77 W-300 360 engine rubber isolators, a pair, to support tailshaft. Too old, hard and solid, something softer much better to handle vibes & shutdown shake.

Dodge says NO FLAME CUTTING/WELDING ON FRAMES! That's why I used all bolt-in components, and ground out old frame rivets to remove problem pieces. I noticed a clear difference in frame metal quality between '67 Townie frame and '78 D-200 donor frame metals. '78 frame, dull yellow sparks when grinding, '67 bright blue white! That means a much higher carbon & nickle content in earlier frame, more robust!

For driveshafting I use ONLY Tom Wood Custom driveshaft out of Utah! I sent him a forward yoke & he fabbed a complete custom shaft cheaper than I could get my old one cut & welded in a big city! $350-$400 to get shaft cut/welded [checked 4 different shops], Tom Wood Custom Driveshaft unit, complete new custom: $150, INCLUDING SHIPPING! He's very well respected for highest quality work available anywhere, the best of the best.

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