need help custom fitting Frogg Toggs pants

I've never altered frogg toggs, but you will probably want to consider either a polyurethane or silicone sealer. My intuition would say that poly would cling better than sil to the fabric, but you may want to try some tests. If they are just pants though, you could probably skip that all together.

check with fabric shops that cater to the outdoors market(questoutfitters, seattle fabrics, owfinc). They might sell seam tape.

Art –

Consider returning the Frogg Toggs and instead purchase the O2 Rainwear gear (http://www.rainshield.com/). BPL lists them both being the same material and construction, but with O2 Rainwear being slightly lighter.

The reason I suggest making this move is because (1) you can purchase O2 rainwear separately (pants/jacket), so you can get the right size for you. I struggled with finding this option with Frogg Toggs. And (2) the sizes of O2 Rainwear aren't nearly as ridiculous when you get them as a set. For example, I'm 6'6" and about 270. I need a XXL rain jacket but only XL pants. With Frogg Toggs, if I got an XXL jacket I also got ridiculously huge pants. With O2 Rainwear when I purchase the set, even though they are both XXL, the pant sizing is more in line with an XL as I guess they figured out that men can have big shoulders but often their shoulders don't match their waists.

Just my two cents – why screw with something to try to make it fit when you can swap it out for pretty much the same material and money to ensure it fits. The only down side, the bright YELLOW color.

Thanks for the feedback so far. The reason I got the Frogg Toggs is because I had a gift card to Dicks Sporting Goods for about $40. Since the Frogg Toggs cost about that much, it was a no brainer. I got the size large set because the medium jacket seemed too small on me. Even with the size medium rain suit, though, the medium pants were really baggy. I think it's possible to buy Frogg Toggs pants separately, but that would eliminate the perceived money savings for me on this item. So maybe I'll give this a shot and see how the seams themselves hold up, without any seam sealer or tape. If not I'll check out the seam tape they sell at Seattle Fabrics, or Quest Outfitters.