Can I switch from a retirement extension to a marriage visa while in Thailand, and what are the implications of timing my trip?

Am currently here on retirement extension but thinking of going to HCMC or Savannakhet and getting a visa based on marriage. My current extension expires on March 10th. Should I plan on making the trip on the 9th and allowing my current extension to expire while I am out of country or can I go and get this new visa prior to the expiration of my extension? If the latter, will this present any problems upon reentering Thailand? I'm assuming with this type of visa my wife will still need to report that I am living in her residence every time I stay outside the home and return.