You'll have to check if you have a hose connected to your oil pan. Not sure what models/engines have it (or if someone was able to add one at some point.) If that is there, you can drain out the bottom. If it's not, you'll have to use an extractor.
And for the RV antifreeze, pull your thermostat out, attach a hose to your raw water pickup (you may be able to pull it off the transmission cooler and either create a fitting or just stuff the hose into the transmission cooler, place the other end in a bucket of antifreeze and start it up. I run 6 gallons through my system. I don't drain it but I know many people are more comfortable draining it once they are done. It's all up to you.
Former owner of a 1987 Supra Saltare. Current owner of a Malibu 23LSV.