I've got a 76 Model 242 Volvo (B21F) that I've owned for several years. When I bought the car for my daughter, it was running great....until she drove it about 8 miles with absolutely no coolant in the radiator. The engine got hot enough to melt the corner off of #3 piston.

I've finally decided to fix this car to cruise around in.
It has a M46 gear box with OD.
The body is solid, and the interior is pretty good considering the age of the car.
I plan on painting it and getting it looking sharp.

I have a good B230 engine on a stand in my shop.
My question regards using the B230 engine by swapping the B21 head onto the B230 engine block.
Will that work?
I have enough fuel injection and ignition parts to put it back together...I'm just not sure if the B21 Head will work on the B230.

I have another option.
I have a (wrecked) 81 Model 240 with a B21F engine. The engine ran good before my son wrecked the car, but the engine did have what I think was a slight knock in the rear main bearing when the engine was first started.
I also have a good crankshaft out of a 76 model B21F.
I had this crank turned to .030" undersized on the Main bearing journals, and the rod bearing journals miked and polished about 10 years ago when I had other plans for this engine.
I could put the good (reground) crankshaft into the B21 from the wrecked car.
If I did this I would go ahead and do a complete rebuild....rings, rod bearings, main bearings (which I already have) and valve job.
The next question.....Will the crankshafts interchange between a 81 Model and a 76 Model B21F engine? I'm thinking that they will but I want to be sure.

What I want ultimately is a sharp 76 Model 242 that I can drive for the rest of my life.
I plan on putting a lot of new parts on the car and making it dependable enough to drive to California if I wanted to (which I don't). You get the idea.

I'm gonna move the car into my shop from my boneyard in the next couple of weeks and start work on it. I will fix it mechanically and then start on
on the body prep.
The car is white at present, and I plan on keeping it the same color.
I haven't decided on the wheels....whether to stay with factory wheels and caps, or to put some sharp aftermarkets on it....time will tell.

Thanks for any advice or response
steve