Need Some Math Help

So I have been hearing about slot machine progressives can provide an advantage if large enough. I just recently went to my local casino to try to run some numbers on the Blazing 7's 3 reel single line progressives they have there. 25c Denom. 3 coin max machines. Here's what I came up with, any help/feedback would be greatly appreciated!

.50c per spin (2coins)
800 Spins

$400 playthrough
total loss = $71
1% of bet went to progressive.
$71 / $400 = 17.75% - 1% = 16.75% Loss Rate

Reel 1- 50 B7's = 1:16
Reel 2- 55 B7's = 1:14.54
Reel 3- 57 B7's = 1:14.03

(Although these show a bit better, I decided to run my numbers based on 1:16 for each of the reels.
I have seen those numbers posted on other forums, so I figure I might have been running just
slightly ahead on the 800 spins I have done.)

16 X 16 X 16 = 4096
4096 X .75c = $3072 playthrough to hit jackpot.
$3072 X 16.75% = $514.56 Breakeven

I did round a few numbers. I believe the percentage toward the jackpot was slightly higher than 1% but I am not too concerned about that. My main concern is with how I did my math, whether I was correct in all my thinking in that regard. These particular machines have a reset value of $500 as well. If I need to provide any other information I will do my best in doing so. Thanks again for any help you can/will provide!

Can you confirm whether the B7 count was for B7s on the payline only or did it include above and below the payline? On 1 line games, they will normally have a much higher weight on the blanks above and below the top award symbol.

My B7 count was on the single payline only. Not counting when the payline hit the blank with the B7's just above or below that.