Ideally, I'd suggest running a 12 wk test cycle to start, but if you wanted to give a try to a low dose of dbol, you can make some gains. Just keep the dose lower and use it for no longer than 4-6 wks. A lot of the gains you make are going to be water retention that you'll shed after the cycle, but you can gain a few lbs of new muscle in the process. When I first started gear, I only used about 15mg dbol a day and gained a a ton...having a hard time remembering the actual scale number, but my weight sky rocketed. I will say that for my next cycle, I ran a little test and then I started to make REAL progress. Back when I started, I knew very little about AI's or SERMs. Back in the day, there was no such thing as PCT and estrogen was much harder to manage. Today, things are easier. Better drugs and better info is available. Dbol has a high rate of conversion to estrogen, so you'll want to keep a close eye on it. Adex through the cycle at a low dose and some nolvadex in case you notice gyno coming on, would both be good to have. Adex will control conversion to estrogen. If conversion is still too high and you get sides, you can pop some nolva for a few days to stop estrogen from binding to the recoptor while you increase the adex to reduce further conversion. Here is how I would lay it out :

1-6

Dbol 25mg, split into 3 doses a day

adex .5mg 2x wk, more if needed

Nolvadex, 20mg a day, if you start to get gyno and at that point, increase adex to .5mg EOD 

a day after you stop dbol, start PCT, You can use the nolvadex 40mg ED for 1 wk. Then 20mg ED for 2 more wks. 

As for drug screening, you will not have to worry about AAS and your CDL. They're testing for rec drugs. The only BB supp that I have heard of having a problem is the ECA stack, sometimes shows up as speed.