Well here are a few assumptions I would make:
1. Samenole - Has two cards 8 or better down. If he is a thinking player in the least he shouldn't be getting to 5th street if this weren't the case (he has to assume that he is in the middle of two very strong hands and might have to call several bets to see 5th)
2. Guy - Has at least one very strong card (I would assume at least an ace or a two) in the hole. For the sake of looking at the best case scenario for your hand let's assume that he doesn't have two
Here is what came up when I ran the simulation
| Hand | Pot equity | Wins | Ties |
|---|
| 4568Q | 25.25% | 151,101 | 781 |
| (2- K 3)45 | 52.05% | 311,639 | 1,286 |
| (8- 8- 7)72 | 22.70% | 135,918 | 618 |
However if "Guy" was in the pot on 3rd street with a 3 card hand (very likely) then you are in an awful situation
| Hand | Pot equity | Wins | Ties |
|---|
| 4568Q | 15.96% | 93,709 | 4,091 |
| (8- 8- 3)45 | 70.35% | 419,755 | 4,681 |
| (8- 8- 7)72 | 13.69% | 81,808 | 685 |