Bob-
As a last recommendation, make sure the charger you pick will be able to fit in the place that you have in mind. Additionally, they have a built-in fan, so it should have adequate ventallation. If things haven't changed, these were the following dimensions:
Model PD-9130, 30 Amp dimensions: 4. 5'' x 7'' x 7. 25'' 4. 0 lbs.
Model PD-9140, 40 Amp dimensions: 4. 5'' x 10'' x 7. 25'' 5. 4 lbs.
Model PD-9145, 45 Amp dimensions: 4. 5'' x 10'' x 7. 25'' 5. 4 lbs.
Model PD-9155, 55 Amp dimensions: 4. 5'' x 10'' x 7. 25'' 5. 4 lbs.
Model PD-9160, 60 Amp dimensions: 3. 6'' x 8'' x 9. 00'' 5. 8 lbs.
Model PD-9180, 80 Amp dimensions: 3. 6'' x 11'' x 9. 00'' 7. 5 lbs.