Good to hear you're going with a Test only cycle - you may want to consider even throwing in a Dianabol kickstart. 0.25mg Adex EOD would be a safe protocol but I got away without needing one at 500mg/week.
But yep, minimum 10 weeks, I'd push for 12 because results won't really kick in till around week 5-6, hence the suggested Dianabol kick start (30-40mg/day, weeks 1-4). Test E you'll only need to shoot twice per week as its a longer ester - three times will just cause unnecessary site injection pain.
500mg is ideal, I've run up to 750mg but found there was no real benefit or different. I've also ran up to 1g for a few weeks and can tell you I got better results on 500-750mg and felt much better, but if you decide to up the dose make sure you place a greater emphasis on the Adex.
I'd personally suggest:
Weeks 1-4: 30-40mg Dianabol/day
Weeks 1-12: 500mg Test E/week
Weeks 1-13: 0.25mg Adex/EOD
Week 14: 0.125mg Adex/EOD
Weeks 15-18: 20mg Nolva/day
Even throw DAA in there around PCT (3g a day). Depending on how easily your body bounces back, this should be ideal - I recovered far more quickly than I thought I would and lost next to nothing post cycle - although I did put on fat. If all goes to plan you'll love the cycle and the results just as I did. Good luck