Community Forums:

Bolt in? Well........No.

Is it possible? You bet. Lots of work. Not cheap.
What are your goals? You want 150 horses with a smooth idle? You can have this with using the Premier three liter block without internal mods.
Clean up the exhaust ports......as in all PRV two valve engines they need help!!
Use the throttle body as installed on the Volvo B-280. It will bolt right up to the Premier/Monaco intake manifold and is much larger then the Monaco throttle body as well as placing the throttle plate at an angle that will make it easy to do an air filter in your D.
Buy the headers that DMC Houston is selling and install them. Just do it.
Get yourself a programmable fuel and ignition system that will allow you to use the trigger wheel that is used on the Premier and adapt as needed. I use Electromotive for the wasted spark arrangement. No distributor. This is a GOOD thing.
Want more power? B-280E cams with the Volvo rocker arms P/N 271617 will give noticeably more top end. With the B-280E cams you will then 'get' to adjust the valves. The Premier/Monaco engine uses hydraulic lash adjusters built into the rocker arms. They work good, but the cams are intended for a 'Merikanski boat like car with an automatic box. Yuck.

In doing any of these engines you will have to transfer the lower case from your D's engine (everything below the centerline of the crankshaft) to your new engine. *Presto!! It is more or less a bolt-in.
All of your accessory drive from your D can be bolted right onto the Premier or B-280 engine.

I would not build one of these engines without the 93mm boresize of the Premier engine. More displacement is always our friend as long as the rules allow it.

Have fun with your project.

John Lane. Oh.....the figure is 500 horses guys. Heehee.