There are a select few Bonnevilles (particularly in Northern climates) that have block heaters installed. If you have it, use it.
If you have a garage and a trickle charger, I would keep the charger on it overnight. Not so much to charge the battery mind you, but to keep it warm due to current flow, and makes for a much stronger battery for cranking. Speaking of batteries, check those date codes on the casing. Batteries *usually* have about a 5 year lifespan, and Murphy'* Law states that winter is when a battery will meet its demise. For someone that does not know, look for a sticker that looks like this:
A-L coresponds to Jan-Dec, number to the right of the dash denotes last digit of year. If your sticker shows a 1 as the year code, now would be a good time to get that battery tested.
If you have a remote starter installed, check to see if it has a temp sensor and will autostart itself if it gets below a certain temp. On the flip side, make sure this function is off if the car is in a garage...carbon monoxide poisoning is something I don't like to think about
Welcome, downwardly mobile yuppies, to the dawn of the Age of Nefarious.
1993 SSEi - FrankenJinx - dead and gone.
1994 SSE (136K strong) - 180* t-stat,HD alternator, most unequipped SSE on the club, XM radio, Kenwood CD/MP3.
2006 Chevy Malibu Maxx LTZ - Custom 2.25" manifold-back exhaust w/FM-80. Probably the only Maxx with this system.