With rough interior probably $5000 - $6000. With good interior and nice hull $7000 - $8000

2nd picture to the left of the arrow that hole is for a dipstick. If you have an oil dipstick that goes into the oil pan this hole should be plugged. When I replaced my 351W long block it had this extra dipstick hole, I plugged it with a rubber plug and a little heavy duty silicone caulk.
...

I installed this one last fall on my 86 Skier. Verified with them that it is also correct for 351W, works great: https://skidim.com/damper-drive-plat...all-block.html

Heavy duty version only really needed for higher than original HP engines: https://skidim.com/damper-plate-bw-ford-...

Skidim said 1516 will hit bell housing of Indmar

86 Skier with new ATK 351W long block. Engine running good but developed noise at transmission in neutral & low speed. Thought it was trans. Changed fluid a couple of times no change. Though I was in for trans re-build over the winter. Did some more research and found Ron Tanis Youtube video on...

I installed new ATK long block and noticed this same phenomena during the break-in procedure. Research I have done indicates it might be normal, heat cycles turn new oil dark quickly. Experts what say you?

Valvoline VR-1 Info

Valvoline VR-1 Info: https://www.valvoline.com/about-us/faq/racing-oil-faq

Mobil 1 Engine Oil Product Guide

I found this should be helpful for the oil conversation.

Mobil 1 Engine Oil Product Guide: https://mobiloil.com/~/media/amer/us...pecs-guide.pdf

Answering my own post

Answering my own post for FYI. Purchased a new ATK DMA1 351W marine long block directly from ATK (www.gearheadengines.com). Sale and shipping very smooth. The DMA1 is the newer version of the 351W with one piece rear main seal and dipstick hole in the block. Boat...

Agreed, 19 Skier she is.

She runs!

She runs!

https://photos.app.goo.gl/P8HKsjbMugYwbW6q8

Couple more pics

Couple more pics...

More pics of 86 engine project

More pics of 86 engine project...

Great job so far!

Think 85 should have fiberglass stringers, my 86 does.

Chris Z

https://photos.app.goo.gl/XJjVVGvg5iUF6w6h8