I had the same exact problem today in southwestern VA---20" snowfall overnight, and my PT425 was under shed roof ready to go. Only problem was the deep snow AND the fact that I had to go up a pretty steep hill to get to my driveway. Shoulda' moved the tractor last night, but then it woulda' been full of snow! Anyhoo, I managed by using the 5' plow to skim layer by layer inching forward bit by bit. I have used the light materials bucket with success, but today the snow blade took the cake. The left-right angling of the blade is very helpful---you can go into the snow forward w/ blade vertical and straight ahead, and as the snow starts to build up, tilt the blade up to scoop up a load, and then use the right-left angle as you are lifting it to chute the load to whatever side you want. I managed to do the 900' driveway today (took 4+ hr), and the blade saved the day.
I had chains on all 4 wheels today. In the past, I used chains only on the front, but I wasn't fooling around today. I got my chains from
www.tirechains.com out of Johnstown, PA. I've ordered stuff from them twice and they are excellent to work with---the stuff you want is in stock, and they ship same day, and prices are great. For the PT425 I am using GT18-2 -Two Link Heavy Duty Tractor Chains fitted to my standard BAR tread tires. I would caution about two things:
1) think twice before getting chains with an aggressive cleated link pattern if you have a finished asphalt driveway. Those chains will eat your driveway for lunch. I had no problems with "HD" chains on all 4 wheels today.
2) I would also caution that if you get chains for a PT, do not get ATV chains. Most ATV chains are made for ATV tires which are much rounder at the shoulders than the PT wheels. The folks at tirechains.com will point you in the right direction.
My driveway is about 200' downhill and 700' uphill, and I have to plow up hill to get to the street. The 6-way action of the blade, especially the left-right when the blade is up in the air and tilted back is a very effective technique to chute snow out of the path you are making.
I would definitely not want to make a living doing this with a PT425 in 20" snow on 900' driveways. Me thinks it would be better to have a PT snowblower attachment for that scenario. Today was a very long day, but a satisfying one. We may see more of this white stuff here next week to finish out a year which has been one of the top 5 wettest years in this area.