Make sure you check with other collectors before you invest in parts from Empire.

If you are using a 327, using a 288 head will increase your compression to 7.5 to one. A small amount of head planing will increase that slightly.

About the gas pedal starter. If you just push the accelerator down until the switch makes contact I believe you will have little trouble with the car flooding. If the carburetor is set properly, you can press the pedal completely to the floor, the carburetor will dump the extra fuel and reduces the potential of flooding. If the engine doesn't start keep the pedal on the floor and use the switch for additional starting attempts.
I own several of the bathtub Packards and have for more than 30 years.
PS if you didn't know your car is a 49 23rd series car. Packard split the 49 into both 22nd and 23 series.
Good luck with your restoration. If I can help in any way just let me know.

Sorry. My intent was that is was suffixed to the model number. Which of course is just before the serial number.
Sorry for the confusion.

I just joined the information site. You may already have found your answer. But.
The R9 used the indicator light but the R11 does not. In fact the solenoid does not have the contacts to energize a light. It only has two not 4. The R9 solenoid will not fit the R11 overdrive. Both of my Super Eight convertibles use the R11.
In fact Packard switched from R9 to R11 during the 22nd series production run.

I have two of the 22nd series convertibles. All convertibles for this series were either Customs or Super eights. The custom had the 356 engine and the Super had the 327 engines. Packard suggested the use of the 288 head on the 327 to increase the compression ratio. So the head is not adequate for ID. The 22nd and 23rd series engines had the serial numbers on the drivers side of the block just below the head. the pad is located almost in the center of the block from back to front. The numbers listed by BigKev are correct.

The serial number tells you if the car was sold as a 48 or 49. is the number is suffixed by a -9, the car was sold as a 49. They did the same trick for the 23rd series cars and used a -5 for the 1950 cars.

Let me know if I can help in any way. I love these cars.