How do I get to the coils to ohm them out?

The Link Below will give you the Service Manual for your dryer. The pertinent parts for you begin on page 8-1:

MDG5500 Service Manual

Do not try to ohm out the gas coils because they will likely show as good with your meter.

It's likely one of the coils is opening a break in the coil as the coil heats up. This coil will shrink when cool and be able to run again (and will likely measure good when cool). The number for the coil kit, which will replace ALL the coils, for your machine is 279834. Replace All coils with Kit Number listed above. Take care not to touch or hit the ignitor or you will be replacing it also. It is VERY brittle.

Disconnect power and turn off gas before working on this dryer. Working on gas dryers is not recommended for people who are not professionals.

Service on gas appliances should be undertaken by professionals only due to the danger of gas leakage which can cause fires or death by asphyxiation.