Back From the Machine Shop and Initial Procedures
After numerous calculations and drop-ins at the machine shop, the 400 block and crankshaft are both in our hands once again and the combo is ready for pre-assembly. Here's how we got started.

Installing Expansion and Oil Galley Plugs

We started off by unloading the block and setting it gently on the garage floor.		No engine stand yet, we needed to install the rear cam retainer since the back of the block would be inaccessible once on the stand.
Installing the rear oil galley plugs is not critical during the mockup stage but while we had the expansion plug set out, we screwed them in using a light amount of RTV. The rear oil galley plugs are pipe threaded for a tight interference fit.		With the block now on the engine stand we installed the six expansion plugs, also with some RTV.
For the sake of consistency, we installed the front oil galley plugs.		These plugs are adjacent to the front cam bore and are not pipe threaded like the rear plugs. We screwed them in firmly with RTV.
At this point we chased the main cap bolt holes with a tap. The same was done to the cylinder head bolt holes. Subsequently, the block was cleaned using compressed air, brake cleaner, and lint-free wipes.

Installing Camshaft
With full access to the 5 cam bores, now was a good time to install the camshaft even though we wouldn't be degreeing the cam and checking piston-to-valve clearance until other critical measurements were taken.

Special attention was paid to the cam bearings, being sure they were wiped free of any dust and small particles.		Each cam bearing was coated with Comp Cams Pro Cam Lube.
The cam was carefully threaded through each cam bore while being sure not to gouge a cam bearing.		We chose to use this Comp Cams Thrust Bearing Cam Retainer Plate instead of the factory plate. The assembly does require special machining of the cam sprocket for use.
Next, we secured the cam by installing the retainer. Finger tight is OK. Remember, we'll be going back through these areas during final assembly.		With the cam installed, we rotated it by hand at the dowel pin in order the coat the lobes with the same Comp Cams Pro Cam Lube used in Step 2 above.
Of course, pre-assembly wasn't completed in just one evening. Therefore, it's a good idea to keep your motor covered when time expires, especially with assembly lubricants acting as fly traps for dust.

(Pre-Installing Crankshaft and Checking Main Bearing Clearance)