I recently acquired an 1100 that on closer inspection may be older than I originally thought. Correct me if I'm wrong on the following:

The serial number does not have a letter prefix (1611XXV) so that would make it pre 1968?

I got it with 2 barrels. One is a 26" Skeet choke with date code "LM" which would make it 1965 or 1992? Since it doesn't have a warning label stamped on it I'm thinking 1965.

The other is a 28" Mod. with a warning label stamped "A(?)K which would make it 1963 or 1990. I think not 1963 because of the warning label.

So, if it left the factory with the skeet barrel that would make it a 1965 gun, yes?

The forend is cracked pretty bad so I'm thinking of doing a fiberglass patch on it. Any suggestions on where to get the fiberglass and resin without having to buy mass quantities of the stuff just to do this one small job? Didn't Remington at some point start reinforcing the forends with fiberglass on the inside? Any idea when that was?

Thanks in advance...

It is pre-68.
Your guesses on the barrels look good. If the Skeet barrel is original the gun should be stamped Skeet, but you can not bet on Remington's rollmarking. Barrel may not be original, no way to know. I bought a 26" plain (no vent rib) Skeet extra barrel special order for my 1100 back in 1963.
Brownells has what you need to fix you fore end and probably so does the local auto parts store and WalMart. Remington did add fiberglass reinforcement in the fore ends later on.

Glad you pointed that out Virginian. I believe my 1100 purchased new in 80 "believe it was made in 79" has what appears to be the fiberglass reinforcement in the forearm.

You might try an auto parts store. I once got a little fiberglass patch kit, a piece of fiberglass matt, resin, hardner and a spatula to spread the mixed resin, at such a store.

Thanks. I picked up some resin and fiberglass cloth at Lowe's. We'll see how it works.

You need to remove some wood before fiberglassing so you retain the original dimensions/fit.

Thanks, will do that.