Forum adverts like this one are shown to any user who is not logged in. Join us by filling out a tiny 3 field form and you will get your own, free, dakka user account which gives a good range of benefits to you: No adverts like this in the forums anymore. Times and dates in your local timezone. Full tracking of what you have read so you can skip to your first unread post, easily see what has changed since you last logged in, and easily see what is new at a glance. Email notifications for threads you want to watch closely. Being a part of the oldest wargaming community on the net. If you are already a member then feel free to login now.

How do these modifiers translate into 5th edition? are they just totally ignored/obsolete and people should just not spend the points on them?

By the letter of the rules, well, they should probably just be ignored.
However, if they were translated into 5th Ed terms, what would be the ramifications?

Ie, Thornback would make a Carnifex who won combat by 2 wounds cause a ld test at -4.
Die Hard guardsmen would just ignore the negative modifiers in combat.
etc.

Are there any immediate situations you can think of that this (perhaps as a house rule) would be incredibly unbalanced?

(backstory)
The guard player in our group seems to think that guard are the most underpowered army in existence; he has some troops nicely modelled as Die-Hards. yet he keeps trying to use the excuse that 'guard are so weak in 5th ed' to bend/break the rules in his favor to 'compensate for the disadvantage of playing guard' (he lists having Jump Packs, Monstrous Creatures and tough Tanks as advantages but seems to ignore the advantages of having 90 deepstriking infantry who can control objectives, or the fat that he has over 200 models in his 2000pt army)
Anyway, he wants to use Die Hards as a 'ignore negative Ld modifiers for being beaten in combat'. I'm reasonably ok with that (more the fact from his modeling than anything else). Yet the Nidzilla player in the group wants the same thing to translate to Thornback - and i can see a lot of imbalance coming in there.

There is precedence for using wounds instead of outnumbering. They are specific to certain FAQs though.
As it stands they are upgrades/wargear options that cost points for no use.

shrug

Like it has been said, both items are useless now.